Unknown vintage frame from Belgium, De Rosa, Clemenso?

I think this is a Hercka. Belgian built by a builder called Clemens. Hercka went on to sell bikes under the name Clemenso, following the Italian trend. They had a pro team, and during the crossover the kit said Hercka and Clemenso. No idea what tubing it is. Though same dimensions as Columbus SLX. Seatpost on mine is 27.2 The lugs are Bocama